Extending LVM By Adding New Disk To a Virtual Machine

In previous post, we have covered the way to make LVM and filesystem aware of the disk size increase that happen in the virtual machine layer. 

There is another way to increase LVM volume capacity, that is to add new disk into the system. 

1. First, shutdown the virtual machine

2. Add a new virtual disk size into the virtual machine manager

3. Start the virtual machine

4. Check the new disk availability for LVM

$ sudo lvmdiskscan

5. To be able to use the new disk, it needs to be converted into physical volume (PV)

$ sudo pvcreate <path to the new disk>

6. Check list of PVs. Memorize the PV name

$ sudo pvs

7. Extend the volume group using the new PV

$ sudo vgextend <VG name> <PV name>

We can get the name of the VG by using this command. This command also will show how much free space is now available in the VG.

$ sudo vgs

8. Increase the size of logical volume, to use 100% of the free space available inside VG, using this command

$ sudo lvextend -l +100%FREE <LV PATH>

We can get the full  path of LV using this command

$ sudo lvdisplay | grep Path

9. Now, make the filesystem aware that the partition size has been increased. The command to do this differ from filesystem to filesystem, but we include 2 of the most used (based on our experience) filesystem

For xfs:

$ sudo xfs_growfs <mountpoint>

For  ext4:

$ sudo resize2fs <mountpoint>

10. Verify that the mountpoint is now increase in size

$ df -Th

Resizing partition in centos after vmware hardisk extension

This is usually done, when the hardisk space for the CentOS VM is running low.

Check your current disk size

# fdisk -lu /dev/sda

To increase the size of the hardisk image, shutdown the centos VM

# poweroff

Increase the hardisk image in VMware

Power on the centos VM

Once logged in, check back whether you have increased your disk size

# fdisk -lu /dev/sda

Create new partition on the new disk space

# fdisk /dev/sda

Press:

n   {new partition}

p   {primary partition}

3   {partition number}

t    {change partition id}

8e {Linux LVM partition}

w  {write partition change to disk}

Reboot the vm

# reboot

Check the new partition

# fdisk -lu /dev/sda

Create physical volume (PV) on the new partition

# pvcreate /dev/sda3

Check list of PV

# pvs

Extend the current Volume Group (VG) to include the new PV, and check the new VG size

# vgextend centos /dev/sda3

# vgs

Extend the current Logical Volume (LV), and check the new size of logical volume 

# lvextend /dev/mapper/centos-root /dev/sda3

# lvs

Resize / partition

# resize2fs /dev/mapper/centos-root

Check the new size

# df -h /

before resize:

after resize:

Cloning virtual machine on vmware esx using vmware-cmd

Below are the steps:

1. List down all the virtual machines that you have

# /usr/bin/vmware-cmd -l
/vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-1/server-1.vmx
/vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-2/server-2.vmx
/vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-3/server-3.vmx

2. Shutdown the machine that you are going to clone. Let say the machine is server-1

# /usr/bin/vmware-cmd /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-1/server-1.vmx stop

3. Use hard stop if you cannot stop it using above command

# /usr/bin/vmware-cmd /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-1/server-1.vmx stop hard

4. Make sure the vm is shutdown by viewing the state

# /usr/bin/vmware-cmd /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-1/server-1.vmx getstate

5. Copy the whole directory

# cp /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/server-1/ /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/newserver/

6. Once done, rename all the files to new name

# rename server-1 newserver /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/newserver/*

7. Change all occurrence of "server-1" to "newserver" in .vmx, .vmdk and .vmxf

# cd /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/newserver/
# sed -i 's/server-1/newserver/g' {newserver.vmdk,newserver.vmx,newserver.vmxf}

8. Edit newserver.vmx file and remove below lines

ethernet0.generatedAddress = "....."
ethernet0.generatedAddressOffset = "....."
uuid.location = "....."
uuid.bios = "....."

9. Add below line to newserver.vmx

uuid.action = "keep"

10. Register your newly cloned virtual machine. Please use the full path to register as below

# vmware-cmd -s register /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/newserver/newserver.vmx

11. Start your new vm after registration.

# /usr/bin/vmware-cmd /vmfs/volumes/47971de9-34657d96-8ac4-001d09068c0c/newserver/newserver.vmx start